drum cartridge

The drum cartridge with a resin connecting frame supported by metal frames and rotatable rollers addresses the issue of drum frame bending, ensuring precise movement and alignment of the developer cartridge, enhancing separation operations in image forming apparatuses.

JP7797945B2Active Publication Date: 2026-01-14BROTHER KOGYO KK
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Patent Information

Application Number
JP2022061488
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2022-04-01
Publication Date
2026-01-14
Estimated Expiration
2042-04-01

AI Technical Summary

Technical Problem

Conventional image forming apparatuses face issues with the developer cartridge moving inaccurately relative to the drum frame due to bending of the drum frame when the spacer member contacts the drum frame, leading to misalignment and precision problems.

Method used

A drum cartridge design featuring a connecting frame made of resin, supported by metal frames, which includes metal frames fixed to the connecting frame with bolts, and rotatable rollers at the separation portions to prevent bending and ensure precise movement of the developing cartridge relative to the drum frame.

Benefits of technology

The design suppresses bending of the connecting frame, allowing for accurate movement and alignment of the developer cartridge relative to the drum frame, reducing friction and misalignment, and enhancing precision during separation operations.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To provide a drum cartridge capable of precisely moving a development cartridge relative to a drum frame by suppressing deflection of the drum frame in separation operation.SOLUTION: A drum frame 60 includes: a first metal frame 63; a second metal frame 64; a connection frame 65; and a first separation part. The first metal frame 63 and the second metal frame 64 are made of metal. The connection frame 65 is positioned between the first metal frame 63 and the second metal frame 64 in a first direction. The first separation part is positioned on the connection frame 65. One portion of a development cartridge abuts on the first separation part in separation operation. The connection frame 65 is connected to the first metal frame 63 and the second metal frame 64. Accordingly, deflection of the first separation part can be suppressed. Therefore, the development cartridge can be moved precisely relative to the drum frame 60.SELECTED DRAWING: Figure 5
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Description

[Technical Field]

[0001] The present disclosure relates to a drum cartridge. [Background technology]

[0002] 2. Description of the Related Art Conventionally, electrophotographic image forming apparatuses such as laser printers, LED printers, etc. A conventional image forming apparatus is described in, for example, Patent Document 1.

[0003] The image forming apparatus disclosed in Patent Document 1 includes a developer cartridge and a drum cartridge. The developer cartridge includes a developer roller. The drum cartridge includes a photosensitive drum. When the developer cartridge is installed in the drum cartridge, the developer roller comes into contact with the photosensitive drum.

[0004] Furthermore, the developer cartridge of Patent Document 1 has a spacer member. The spacer member is movable relative to the housing of the developer cartridge. When the spacer member is moved while the developer cartridge is attached to the drum cartridge, the spacer member comes into contact with the drum frame of the drum cartridge. This causes the developer cartridge to move relative to the drum frame. As a result, the developer roller can be spaced apart from the photosensitive drum. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-113858 Summary of the Invention [Problem to be solved by the invention]

[0006] In this type of image forming apparatus, when the spacer member of the developer cartridge is moved and brought into contact with the drum frame, the drum frame may bend, which poses a problem in that the developer cartridge cannot be moved accurately relative to the drum frame.

[0007] An object of the present disclosure is to provide a drum cartridge that can move a developing cartridge with high precision relative to the drum frame by suppressing bending of the drum frame during a separating operation. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, a first disclosure of the present application provides a drum cartridge to which a developing cartridge having a developing roller can be detachably attached, the drum cartridge including a photosensitive drum rotatable about a drum axis extending in a first direction, a drum frame to which the developing cartridge can be detachably attached, the drum frame including a first side frame located at one end of the drum frame in the first direction, a second side frame located at the other end of the drum frame in the first direction and spaced apart from the first side frame in the first direction, a first metal frame made of metal and attached to an inner surface of the first side frame, and a second metal frame made of metal and having a front The drum frame has a second metal frame attached to the inner surface of the second side frame, a connecting frame located between the first metal frame and the second metal frame in the first direction, connecting the first metal frame and the second metal frame in the first direction, and a first separation portion located on the connecting frame that moves the developing cartridge relative to the drum frame so that the developing roller separates from the photosensitive drum when a part of the developing cartridge moves in the first direction relative to the drum frame while the developing cartridge is attached to the drum frame.

[0009] A second disclosure of the present application is the drum cartridge of the first disclosure, characterized in that the connecting frame rotatably supports the photosensitive drum.

[0010] The third disclosure of the present application is a drum cartridge as described in claim 1 or claim 2, characterized in that the connecting frame has a first end fixed to the first metal frame and a second end located away from the first end in the first direction and fixed to the second metal frame, and the first spaced portion is located at the first end.

[0011] A fourth disclosure of the present application is the drum cartridge according to any one of the first to third disclosures, wherein when the developer cartridge is attached to the drum frame and a part of the developer cartridge moves in the first direction relative to the drum frame, the developer cartridge is moved with respect to the drum frame so that the developer roller is separated from the photosensitive drum, the second separating part being located on the connecting frame. The device further comprises:

[0012] A fifth disclosure of the present application is the drum cartridge according to any one of the first to fourth disclosures, characterized in that the first metal frame is fixed to the connecting frame with bolts.

[0013] The sixth disclosure of the present application is a drum cartridge according to the fifth disclosure, characterized in that the photosensitive drum is located at one end of the drum frame in a second direction intersecting the first direction, and in the second direction, the bolt is located closer to the first separation portion than the photosensitive drum.

[0014] The seventh disclosure of the present application is a drum cartridge according to the sixth disclosure, wherein the first metal frame has a convex portion that protrudes in the second direction toward the first separation portion, and the convex portion is fixed to the connecting frame by the bolt.

[0015] An eighth disclosure of the present application is the developing cartridge according to any one of the first to seventh disclosures, characterized in that the first separating portion is formed integrally with the connecting frame.

[0016] A ninth disclosure of the present application is the drum cartridge according to the sixth or seventh disclosure, wherein the first spaced portion is a rotatable roller.

[0017] A tenth disclosure of the present application is the drum cartridge of the ninth disclosure, wherein the roller is rotatable about an axis extending in the second direction.

[0018] An eleventh disclosure of the present application is the drum cartridge of the ninth disclosure, characterized in that the roller is rotatable about an axis extending in a third direction that intersects with the first direction and the second direction.

[0019] A twelfth disclosure of the present application is the drum cartridge according to any one of the first to eleventh disclosures, characterized in that the connecting frame is made of resin.

[0020] A thirteenth disclosure of the present application is the drum cartridge according to any one of the first to twelfth disclosures, characterized in that the first side frame is made of resin, and the second side frame is made of resin. [Effects of the Invention]

[0021] According to the first to thirteenth disclosures of the present application, the first separation portion is located on the connecting frame. The connecting frame is connected to the first metal frame and the second metal frame, which are made of metal. This makes it possible to suppress bending of the first separation portion. Therefore, the developer cartridge can be moved accurately relative to the drum frame.

[0022] According to the second disclosure of the present application, the first separating portion is provided on the connecting frame that supports the photosensitive drum, thereby making it possible to prevent the first separating portion from being misaligned with the photosensitive drum.

[0023] Furthermore, according to the third disclosure of the present application, it is possible to suppress the bending of the first and second separating portions, thereby enabling the developer cartridge to be moved with more precision relative to the drum frame.

[0024] According to the sixth disclosure of the present application, the first metal frame is fixed to the connecting frame near the first spaced portion, which makes it possible to further suppress bending of the first spaced portion.

[0025] Furthermore, according to the seventh disclosure of the present application, it is possible to further suppress the bending of the connecting frame in the vicinity of the first spaced portion.

[0026] Furthermore, according to the eighth disclosure of the present application, the number of parts in the drum cartridge can be reduced.

[0027] Furthermore, according to the ninth disclosure of the present application, it is possible to reduce friction when a part of the developing cartridge comes into contact with the first spaced portion.

[0028] According to the eleventh disclosure of the present application, the rollers are arranged along the third direction. This prevents the first spaced portion from protruding in the second direction. As a result, deflection of the connecting frame near the first spaced portion can be further suppressed. [Brief explanation of the drawings]

[0029] [Figure 1] FIG. 1 is a schematic diagram of an image forming apparatus. [Figure 2] FIG. [Figure 3] FIG. 2 is a perspective view of a drum cartridge with four developing cartridges attached. [Figure 4] FIG. 2 is a perspective view of the drum cartridge without a developing cartridge attached thereto. [Figure 5] FIG. 2 is a perspective view of the drum cartridge with the first side frame and the second side frame removed. [Figure 6] FIG. 6 is an enlarged view of region A in FIG. 5. [Figure 7] FIG. 1 is a perspective view of four connecting frames and one developing cartridge. [Figure 8] FIG. 1 is a perspective view of four connecting frames and one developing cartridge. [Figure 9] FIG. 8 is an enlarged view of region B in FIG. [Figure 10] FIG. 9 is an enlarged view of region C in FIG. [Figure 11] 10 is a view of a first spaced portion according to a first modified example, viewed in a first direction. FIG. [Figure 12] 10 is a view of a first spaced portion according to a second modified example, viewed in a first direction. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0031] In the following description, the direction in which the drum shaft of the photosensitive drum extends is referred to as the "first direction." The direction in which one end of the drum frame where the photosensitive drum is located is aligned with the other end of the drum frame is referred to as the "second direction." The direction in which the four photosensitive drums are aligned is referred to as the "third direction."

[0032] The first direction and the second direction intersect (preferably perpendicular to) each other. The second direction and the third direction intersect (preferably perpendicular to) each other. The third direction and the first direction intersect (preferably perpendicular to) each other.

[0033] <1. Configuration of image forming device> FIG. 1 is a schematic diagram of an image forming apparatus 100. The image forming apparatus 100 is an electrophotographic printer. Specifically, the image forming apparatus 100 is a laser printer or an LED printer. As shown in FIG. 1, the image forming apparatus 100 includes a main body frame 101, a drum cartridge 2, and four developing cartridges 1.

[0034] The four developer cartridges 1 are detachable from the drum cartridge 2. Furthermore, the drum cartridge 2 to which the four developer cartridges 1 are attached is detachable from the main body frame 101.

[0035] The four developer cartridges 1 contain developers of different colors (e.g., yellow, magenta, cyan, and black). The developers are, for example, toner. The image forming apparatus 100 prints an image on the surface of printing paper using the developers supplied from the developer cartridges 1.

[0036] <2. Structure of the developing cartridge> 2 is a perspective view of the developing cartridge 1. As shown in FIG. 2, the developing cartridge 1 includes a housing 10, a developing roller 20, a gear portion 30, and a spacing member 40.

[0037] The housing 10 is a container capable of containing a developer. The housing 10 has a first outer surface 11 and a second outer surface 12. The first outer surface 11 is located at one end of the housing 10 in the first direction. The second outer surface 12 is located at the other end of the housing 10 in the first direction. The first outer surface 11 and the second outer surface 12 are spaced apart from each other in the first direction.

[0038] A storage chamber 13 is provided inside the housing 10. The developer is stored in the storage chamber 13. The housing 10 also has an opening 14. The opening 14 is located at one end of the housing 10 in the second direction. The external space of the housing 10 and the storage chamber 13 communicate with each other via the opening 14.

[0039] The developing roller 20 is a roller that can rotate about a development axis that extends in the first direction. The developing roller 20 is located in the opening 14 of the housing 10. That is, the developing roller 20 is located at one end of the housing 10 in the second direction. The developing roller 20 has a developing roller main body 21 and a developing roller shaft 22. The developing roller main body 21 is a cylindrical member that extends in the first direction. The developing roller main body 21 is made of, for example, elastic rubber. The developing roller shaft 22 is a columnar member that penetrates the developing roller main body 21 and extends in the first direction. The developing roller main body 21 is fixed to the developing roller shaft 22. The developing roller shaft 22 is made of metal or conductive resin.

[0040] The developing roller 20 rotates about its development axis by a driving force supplied from the image forming apparatus 100. The developer in the housing 10 is carried on the outer surface of the developing roller 20.

[0041] The gear unit 30 is located on the first outer surface 11 of the housing 10. The gear unit 30 has a gear cover 31, a coupling 32, and a plurality of gears. The gear cover 31 is fixed to the first outer surface 11 of the housing 10. At least some of the plurality of gears are located between the first outer surface 11 and the gear cover 31 in the first direction.

[0042] The coupling 32 is exposed from the gear cover 31. When the drum cartridge 2 with the developer cartridge 1 attached thereto is installed in the image forming apparatus 100, the drive shaft of the image forming apparatus 100 is connected to the coupling 32. Then, the rotation of the drive shaft is transmitted to the developing roller 20 via the coupling 32 and the gear.

[0043] As shown in FIG. 2, the housing 10 has a housing groove 15 and a housing hole 16. Furthermore, the gear cover 31 has a cover hole 33. The housing groove 15 extends in a first direction on the outer surface of the housing 10. The cover hole 33 is located at one end of the housing groove 15 in the first direction. The cover hole 33 penetrates the gear cover 31 in the first direction at a position overlapping with the housing groove 15 in the first direction. The housing hole 16 is located at the other end of the housing groove 15 in the first direction. The housing hole 16 penetrates the housing 10 in the first direction at a position overlapping with the housing groove 15 in the first direction.

[0044] When the drum cartridge 2 with four developer cartridges 1 installed is mounted in the image forming apparatus 100, the image forming apparatus 100 can perform a separation operation for each developer cartridge 1. The separation operation is an operation of moving the developer roller 20 from a contact position where it contacts the photosensitive drum 50 to a separation position where it is separated from the photosensitive drum 50. The image forming apparatus 100 performs the separation operation for the developer cartridge 1 that is not being used out of the four developer cartridges 1. As a result, the developer roller 20 of the developer cartridge 1 that is not being used is separated from the photosensitive drum 50.

[0045] The spacing member 40 is a mechanism for switching the developing roller 20 between the contact position and the spaced position described above. The spacing member 40 is located between one end and the other end of the housing 10 in the second direction. As shown in FIG. 2, the spacing member 40 has a first cam 41, a second cam 42, and a shaft 43.

[0046] The shaft 43 is disposed in the housing groove 15. The shaft 43 extends in a first direction along the housing groove 15. The shaft 43 is inserted into the cover hole 33 and the housing hole 16. The shaft 43 is, for example, cylindrical. However, the shaft 43 may also be prismatic.

[0047] The first cam 41 is located at one end of the shaft 43 in the first direction. The first cam 41 is located on the first outer surface 11 of the housing 10.

[0048] The first cam 41 has a first inclined surface 411. The first inclined surface 411 is located on a part of the circumferential surface of the first cam 41 centered on the shaft 43. The first inclined surface 411 is inclined in a first direction. More specifically, the first inclined surface 411 moves away from the shaft 43 in the radial direction relative to the shaft 43 as it moves away from the other end of the shaft 43 in the first direction. Furthermore, the first inclined surface 411 moves closer to the developing roller 20 as it moves away from the second cam 42 in the first direction.

[0049] The second cam is located at the other end of the shaft 43 in the first direction. The second cam is located on the second outer surface 12 of the housing .

[0050] The second cam 42 has a second inclined surface 421. The second inclined surface 421 is located on a part of the circumferential surface of the second cam 42 centered on the shaft 43. The second inclined surface 421 is inclined in the first direction. As the second inclined surface 421 moves away from one end of the shaft 43 in the first direction, it approaches the shaft 43 in the radial direction relative to the shaft 43. Furthermore, as the second inclined surface 421 moves away from the first cam 41 in the first direction, it moves away from the developing roller 20.

[0051] The spacing member 40 is movable in a first direction between a first position and a second position relative to the housing 10 and the developing roller 20. The movement from the first position to the second position is a movement in a direction from the first cam 41 toward the second cam 42.

[0052] The developer cartridge 1 also has a spring (not shown). The spring is an elastic member that is expandable and contractible in a first direction. The spring urges the spacing member 40 in the first direction, from the second position toward the first position. Therefore, when the spacing member 40 is not pressed by the pressing shaft 102 (described later), the spacing member 40 is located at the first position.

[0053] The spacing operation using the spacing member 40 will be described in detail later.

[0054] <3. Drum cartridge configuration> Fig. 3 is a perspective view of the drum cartridge 2 with four developer cartridges 1 attached. Fig. 4 is a perspective view of the drum cartridge 2 without any developer cartridges 1 attached. Fig. 5 is a perspective view of the drum cartridge 2 with a first side frame 61 and a second side frame 62 (described later) removed.

[0055] As shown in FIGS. 3 to 5, the drum cartridge 2 includes four photosensitive drums 50 and a drum frame 60.

[0056] The four photosensitive drums 50 are supported by a drum frame 60. The four photosensitive drums 50 are located at one end of the drum frame 60 in the second direction. The four photosensitive drums 50 are arranged at intervals in the third direction. Each photosensitive drum 50 is rotatable about a drum axis extending in the first direction. Each photosensitive drum 50 has a cylindrical outer surface centered on the drum axis. When the developer cartridge 1 is installed in the drum cartridge 2, the outer surface of the developer roller 20 comes into contact with the outer surface of the photosensitive drum 50.

[0057] The drum frame 60 is a frame that supports four developer cartridges 1. The four developer cartridges 1 are attached to and detached from the drum frame 60. As shown in FIGS. 3 to 5, the drum frame 60 has a first side frame 61, a second side frame 62, a first metal frame 63, a second metal frame 64, and four connecting frames 65.

[0058] The first side frame 61 is located at one end of the drum frame 60 in the first direction. The first side frame 61 is generally plate-shaped and extends in the second and third directions. The outer surface of the first side frame 61 becomes the outer surface of one end of the drum cartridge 2 in the first direction. The first side frame 61 is made of resin.

[0059] The second side frame 62 is located at the other end of the drum frame 60 in the first direction. The second side frame 62 is located away from the first side frame 61 in the first direction. The second side frame 62 is generally plate-shaped and extends along the second and third directions. The outer surface of the second side frame 62 becomes the outer surface of the other end of the drum cartridge 2 in the first direction. The second side frame 62 is made of resin.

[0060] The first metal frame 63 is located between the first side frame 61 and a connecting frame 65 (described later) in the first direction. The first metal frame 63 is attached to the inner surface of the first side frame 61. The first metal frame 63 is generally plate-shaped and extends along the second and third directions.

[0061] The first metal frame 63 is made of metal such as iron or stainless steel. The rigidity of the first metal frame 63 is higher than the rigidity of the first side frame 61. The rigidity of the first metal frame 63 is also higher than the rigidity of the connecting frame 65, which will be described later.

[0062] 5, the first metal frame 63 has four first protrusions 631. The four first protrusions 631 are arranged at intervals in the third direction. Each first protrusion 631 protrudes from the first metal frame 63 in the second direction toward a first separating portion 66 (described later).

[0063] The second metal frame 64 is located between the second side frame 62 and a connecting frame 65 (described later) in the first direction. The second metal frame 64 is attached to the inner surface of the second side frame 62. The second metal frame 64 is generally plate-shaped and extends along the second and third directions.

[0064] The second metal frame 64 is made of metal such as iron or stainless steel. The rigidity of the second metal frame 64 is higher than the rigidity of the second side frame 62. The rigidity of the second metal frame 64 is also higher than the rigidity of the connecting frame 65, which will be described later.

[0065] 5, the second metal frame 64 has four second protrusions 641. The four second protrusions 641 are arranged at intervals in the third direction. Each second protrusion 641 protrudes from the second metal frame 64 in the second direction toward a second separating portion 67 (described later).

[0066] The four photosensitive drums 50 are located between the first metal frame 63 and the second metal frame 64 in the first direction. Furthermore, when the developer cartridge 1 is attached to the drum cartridge 2, the housing 10 of the developer cartridge 1 is located between the first metal frame 63 and the second metal frame 64 in the first direction.

[0067] The four connecting frames 65 are positioned between the first metal frame 63 and the second metal frame 64 in the first direction. The four connecting frames 65 connect the first metal frame 63 and the second metal frame 64 in the first direction. Each of the four connecting frames 65 rotatably supports the photosensitive drum 50. Each connecting frame 65 is made of resin.

[0068] The four connecting frames 65 are arranged in the third direction. Each photosensitive drum 50 is located between adjacent connecting frames 65 in the second direction.

[0069] Each connecting frame 65 extends in a first direction. Each connecting frame 65 has a first end 651 and a second end 652. The first end 651 is located at one end of the connecting frame 65 in the first direction. The second end 652 is located at the other end of the connecting frame 65 in the first direction. The second end 652 is located away from the first end 651 in the first direction.

[0070] A first end 651 of each connecting frame 65 is fixed to the first metal frame 63. A second end 652 of each connecting frame 65 is fixed to the second metal frame 64. Therefore, the four connecting frames 65 are positioned relative to each other by the first metal frame 63 and the second metal frame 64.

[0071] Fig. 6 is an enlarged view of region A in Fig. 5. As shown in Fig. 6, a first end 651 of the connecting frame 65 is fixed to the first metal frame 63 with a first bolt 653. Specifically, the first end 651 of the connecting frame 65 is fixed to a first protrusion 631 of the first metal frame 63 with the first bolt 653.

[0072] More specifically, the first end 651 of the connecting frame 65 has a first screw hole (not shown) extending in the first direction. Furthermore, the first protrusion 631 of the first metal frame 63 has a first through hole 632 penetrating in the first direction. The first bolt 653 is inserted into the first through hole 632 and fastened to the first screw hole. This sandwiches the first protrusion 631 between the head of the first bolt 653 and the connecting frame 65. As a result, the connecting frame 65 is fixed to the first metal frame 63.

[0073] Similarly, the second end 652 of the connecting frame 65 is fixed to the second metal frame 64 with a second bolt (not shown). Specifically, the second end 652 of the connecting frame 65 is fixed to the second protrusion 641 of the second metal frame 64 with the second bolt.

[0074] More specifically, the second end 652 of the connecting frame 65 has a second screw hole (not shown) extending in the first direction. Furthermore, the second protrusion 641 of the second metal frame 64 has a second through hole (not shown) penetrating in the first direction. A second bolt is inserted into the second through hole and fastened to the second screw hole. This sandwiches the second protrusion 641 between the head of the second bolt and the connecting frame 65. As a result, the connecting frame 65 is fixed to the second metal frame 64.

[0075] 7 and 8 are perspective views of four connecting frames 65 and one developer cartridge 1. Fig. 7 shows a state in which the separating operation is not being performed, while Fig. 8 shows a state in which the separating operation is being performed.

[0076] Figure 9 is an enlarged view of area B in Figure 7. As shown in Figure 9, the drum frame 60 further has a first spacing portion 66. The first spacing portion 66 is located at a first end 651 of the connecting frame 65. The first spacing portion 66 is a portion that comes into contact with the first cam 41 of the developing cartridge 1 when performing a spacing operation.

[0077] The first separation portion 66 of this embodiment is formed integrally with the connecting frame 65. That is, the first separation portion 66 of this embodiment is a part of the outer surface of the connecting frame 65. The first separation portion 66 has a corner that can come into contact with the first cam 41. By forming the first separation portion 66 integrally with the connecting frame 65 in this way, the number of parts of the drum cartridge 2 can be reduced compared to when the first separation portion 66 is a part separate from the connecting frame 65.

[0078] Figure 10 is an enlarged view of area C in Figure 8. As shown in Figure 10, the drum frame 60 further has a second spacing portion 67. The second spacing portion 67 is located at the second end 652 of the connecting frame 65. The second spacing portion 67 is a portion that comes into contact with the second cam 42 of the developer cartridge 1 when performing the spacing operation.

[0079] The second separation portion 67 of this embodiment is formed integrally with the connecting frame 65. That is, the second separation portion 67 of this embodiment is a part of the outer surface of the connecting frame 65. The second separation portion 67 has a corner that can come into contact with the second cam 42. By forming the second separation portion 67 integrally with the connecting frame 65 in this way, the number of parts of the drum cartridge 2 can be reduced compared to when the second separation portion 67 is a part separate from the connecting frame 65.

[0080] <4. Separation operation> Next, the separation operation of the image forming apparatus 100 will be described.

[0081] The image forming apparatus 100 has a pressure mechanism (not shown). When the drum cartridge 2 with the developer cartridge 1 installed is mounted on the main body frame 101, the developer roller 20 is pressed toward the photosensitive drum 50 by the pressure mechanism. This causes the outer surface of the developer roller 20 to come into contact with the outer surface of the photosensitive drum 50. In other words, the position of the developer roller 20 becomes the contact position described above.

[0082] 9, the image forming apparatus 100 has a pressing shaft 102. When the drum cartridge 2, to which four developer cartridges 1 are attached, is attached to the main body frame 101, the pressing shaft 102 faces the first cams 41 of the developer cartridges 1 in the first direction.

[0083] The pressing shaft 102 is movable in a first direction between a retracted position and a protruding position that is closer to the developer cartridge 1 than the retracted position. When performing a spacing operation, the image forming apparatus 100 moves the pressing shaft 102 from the retracted position to the protruding position. This causes the pressing shaft 102 to come into contact with the first cam 41. The pressing shaft 102 then presses the spacing member 40 in the first direction, from the first cam 41 toward the second cam 42. This causes the spring to contract, causing the spacing member 40 to move in the first direction from the first position to the second position relative to the housing 10. That is, the spacing member 40 moves in the first direction from the first position to the second position relative to the drum frame 60.

[0084] When the spacing member 40 moves from the first position to the second position, the first inclined surface 411 of the first cam 41 moves in the first direction while contacting the first spacing portion 66 of the drum cartridge 2. At this time, the first cam 41 moves in a direction away from the photosensitive drum 50 relative to the drum frame 60 due to the resistance force received from the first spacing portion 66.

[0085] Similarly, when the spacing member 40 moves from the first position to the second position, the second inclined surface 421 of the second cam 42 moves in the first direction while contacting the second spacing portion 67 of the drum cartridge 2. At this time, the second cam 42 moves in a direction away from the photosensitive drum 50 relative to the drum frame 60 due to the resistance force received from the second spacing portion 67.

[0086] As a result, the housing 10 and the developing roller 20, together with the spacing member 40, move in a direction away from the photosensitive drum 50 relative to the drum frame 60. As a result, the developing roller 20 moves from a contact position where it contacts the photosensitive drum 50 to a separation position where it is separated from the photosensitive drum 50.

[0087] During the above-described separation operation, if the first separation portion 66 were to bend due to the pressing force from the first cam 41, it would be difficult to move the first cam 41 accurately in a direction away from the photosensitive drum 50. However, in the drum cartridge 2 of this embodiment, the first separation portion 66 is located on the connecting frame 65. The connecting frame 65 is connected to the first metal frame 63 and the second metal frame 64, which are made of metal. This prevents the first separation portion 66 from being bent. Therefore, the first cam 41 can be moved accurately in a direction away from the photosensitive drum 50.

[0088] Furthermore, if the second spacing portion 67 were to bend due to the pressing force from the second cam 42 during the spacing operation, it would be difficult to move the second cam 42 accurately in a direction away from the photosensitive drum 50. However, in the drum cartridge 2 of this embodiment, the second spacing portion 67 is located on the connecting frame 65. The connecting frame 65 is connected to the first metal frame 63 and the second metal frame 64, which are made of metal. This prevents the second spacing portion 67 from being bent. Therefore, the second cam 42 can be moved accurately in a direction away from the photosensitive drum 50.

[0089] Furthermore, in this embodiment, the connecting frame 65 supports the photosensitive drum 50, and the first separating portion 66 is provided on the connecting frame 65. In this way, it is possible to prevent the first separating portion 66 from being misaligned with the photosensitive drum 50. Therefore, it is possible to move the developing cartridge 1 with respect to the photosensitive drum 50 with greater precision.

[0090] Furthermore, in this embodiment, the connecting frame 65 supports the photosensitive drum 50, and the second separating portion 67 is provided on the connecting frame 65. In this way, it is possible to prevent the second separating portion 67 from being misaligned with respect to the photosensitive drum 50. Therefore, it is possible to move the developing cartridge 1 with respect to the photosensitive drum 50 with greater precision.

[0091] Furthermore, in this embodiment, the first bolt 653 is positioned closer to the first separation portion 66 in the second direction than the photosensitive drum 50. Specifically, the first end portion 651 of the connecting frame 65 is fixed to the first protrusion 631 of the first metal frame 63 by the first bolt 653. In this way, by arranging the first bolt 653 near the first separation portion 66, the first metal frame 63 can be fixed to the connecting frame 65 near the first separation portion 66. This makes it possible to further suppress bending of the first separation portion 66.

[0092] Furthermore, in this embodiment, the second bolt is located closer to the second separation portion 67 in the second direction than the photosensitive drum 50. Specifically, the second end portion 652 of the connecting frame 65 is fixed to the second protrusion 641 of the second metal frame 64 by the second bolt. In this way, by arranging the second bolt near the second separation portion 67, the second metal frame 64 can be fixed to the connecting frame 65 near the second separation portion 67. This makes it possible to further suppress bending of the second separation portion 67.

[0093] <5. Variations> Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments.

[0094] <5-1. First modified example> In the above embodiment, the first spaced apart portion 66 and the second spaced apart portion 67 are formed integrally with the connecting frame 65. However, the first spaced apart portion 66 and the second spaced apart portion 67 may be separate components from the connecting frame 65. For example, the first spaced apart portion 66 and the second spaced apart portion 67 may be rotatable rollers.

[0095] FIG. 11 is a view of the first spacing portion 66 according to the first modified example, viewed in the first direction. The first spacing portion 66 in FIG. 11 is a rotatable roller. The first spacing portion 66 is located on the connecting frame 65. The first spacing portion 66 is rotatable about an axis extending in the second direction. When the spacing member 40 moves from the first position to the second position, the first inclined surface 411 of the first cam 41 moves in the first direction while contacting the outer circumferential surface of the roller of the first spacing portion 66. At this time, the roller of the first spacing portion 66 rotates. This allows the first cam 41 to move while reducing friction between the first cam 41 and the first spacing portion 66.

[0096] 11, during the separating operation, the first cam 41 moves in the third direction relative to the first separating portion 66. Therefore, the developing roller 20 moves in the third direction away from the photosensitive drum 50.

[0097] Similar to the first spaced apart portion 66 in FIG. 11, the second spaced apart portion 67 may also be a roller that is rotatable about an axis extending in the second direction.

[0098] <5-2. Second modified example> FIG. 12 is a view of a first spacing portion 66 according to the second modified example, viewed in the first direction. The first spacing portion 66 in FIG. 12 is a rotatable roller. The first spacing portion 66 is located on a connecting frame 65. The first spacing portion 66 is rotatable about an axis extending in the third direction. When the spacing member 40 moves from the first position to the second position, the first inclined surface 411 of the first cam 41 moves in the first direction while contacting the outer circumferential surface of the roller of the first spacing portion 66. At this time, the roller of the first spacing portion 66 rotates. This allows the first cam 41 to move while reducing friction between the first cam 41 and the first spacing portion 66.

[0099] 12, during the separating operation, the first cam 41 moves in the second direction relative to the first separating portion 66. Therefore, the developing roller 20 moves in the second direction away from the photosensitive drum 50.

[0100] Furthermore, when the first spacing portion 66 is arranged along the third direction as shown in Fig. 12, the position of the first spacing portion 66 can be prevented from protruding in the second direction, compared to when the first spacing portion 66 is arranged along the second direction as shown in Fig. 11. This further prevents the connecting frame 65 from being deflected near the first spacing portion 66 due to the pressing force from the first cam 41.

[0101] Similar to the first spaced apart portion 66 in FIG. 12, the second spaced apart portion 67 may also be a roller that is rotatable about an axis extending in the third direction.

[0102] <5-3. Other variations> In the above embodiment, the spacing member 40 has the first cam 41 and the second cam 42. However, the spacing member 40 does not have to have the second cam 42. Also, in the above embodiment, the drum frame 60 has the first spacing portion 66 and the second spacing portion 67. However, the drum frame 60 does not have to have the second spacing portion 67.

[0103] Furthermore, in the above embodiment, the spacing member 40, which is a part of the developer cartridge 1, is moved in the first direction during the separating operation. However, the part that is moved during the separating operation of the developer cartridge 1 does not necessarily have to be the spacing member 40 as in the above embodiment. It is sufficient that a part of the developer cartridge 1 moves in the first direction relative to the drum frame 60, thereby coming into contact with the first spacing portion 66 of the drum frame 60, and thereby the developer cartridge 1 moves relative to the drum frame 60 in a direction away from the photosensitive drum 50.

[0104] In the above embodiment, four developer cartridges 1 can be attached to one drum cartridge 2. However, the number of developer cartridges 1 attached to the drum cartridge 2 may be one to three, or may be five or more.

[0105] Furthermore, the elements appearing in the above-described embodiment and modified examples may be combined as appropriate within the scope of not causing any contradiction. [Explanation of symbols]

[0106] 1 Developer cartridge 2 drum cartridges 10. Cabinet 20 Developing roller 30 Gear section 40 spacing member 50 Photosensitive drum 60 Drum Frame 61 First side frame 62 Second side frame 63 First Metal Frame 64 Second Metal Frame 65 Connecting Frame 66 1st separation part 67 2nd separation part 100 Image forming device 631 First convex part 641 Second convex part 651 First end 652 Second end 653 First Bolt

Claims

1. A drum cartridge in which a developing cartridge having a developing roller is detachably mounted, a photosensitive drum rotatable about a drum axis extending in a first direction; A drum frame to which the developing cartridge is detachably attached, a first side frame located at one end of the drum frame in the first direction; a second side frame located at the other end of the drum frame in the first direction and spaced apart from the first side frame in the first direction; a first metal frame made of metal and attached to an inner surface of the first side frame; a second metal frame made of metal and attached to an inner surface of the second side frame; a connecting frame located between the first metal frame and the second metal frame in the first direction, the connecting frame connecting the first metal frame and the second metal frame in the first direction; a first separating portion that moves the developer cartridge relative to the drum frame so that the developing roller separates from the photosensitive drum when a portion of the developer cartridge moves in the first direction relative to the drum frame with the developer cartridge attached to the drum frame, the first separating portion being located on the connecting frame; a drum frame having A drum cartridge comprising:

2. 2. The drum cartridge according to claim 1, The drum cartridge is characterized in that the connecting frame rotatably supports the photosensitive drum.

3. 3. The drum cartridge according to claim 1, The connecting frame is a first end portion fixed to the first metal frame; a second end portion located away from the first end portion in the first direction and fixed to the second metal frame; and The drum cartridge, wherein the first spaced portion is located at the first end portion.

4. 3. The drum cartridge according to claim 1, a second separating portion that moves the developer cartridge relative to the drum frame so that the developing roller separates from the photosensitive drum when a part of the developer cartridge moves in the first direction relative to the drum frame with the developer cartridge attached to the drum frame, the second separating portion being located on the connecting frame; The drum cartridge further comprises:

5. 3. The drum cartridge according to claim 1, The drum cartridge according to claim 1, wherein the first metal frame is fixed to the connecting frame with bolts.

6. 6. The drum cartridge according to claim 5, the photosensitive drum is located at one end of the drum frame in a second direction intersecting the first direction, The drum cartridge, wherein the bolt is located closer to the first spaced portion than the photosensitive drum in the second direction.

7. 7. The drum cartridge according to claim 6, The first metal frame is a protrusion that protrudes in a direction approaching the first spaced portion in the second direction and The drum cartridge is characterized in that the protrusion is fixed to the connecting frame by the bolt.

8. 3. The drum cartridge according to claim 1, The drum cartridge according to claim 1, wherein the first spaced portion is integrally formed with the connecting frame.

9. 7. The drum cartridge according to claim 6, The drum cartridge is characterized in that the first spaced portion is a rotatable roller.

10. 10. The drum cartridge according to claim 9, The drum cartridge, wherein the roller is rotatable about an axis extending in the second direction.

11. 10. The drum cartridge according to claim 9, The drum cartridge is characterized in that the roller is rotatable about an axis extending in a third direction that intersects with the first direction and the second direction.

12. 3. The drum cartridge according to claim 1, The drum cartridge is characterized in that the connecting frame is made of resin.

13. 3. The drum cartridge according to claim 1, the first side frame is made of resin, The drum cartridge is characterized in that the second side frame is made of resin.

Citation Information

Patent Citations

  • Image forming apparatus

    JP2019179131A

  • Drawer

    JP2020056817A

  • Drawer

    JP2021113858A

  • Image forming apparatus

    JP2022027022A